Sweet corn! Carp ( And Koi are just colorful carp ) love sweet things, including sweet corn. Chum some out and fish the same area. Remember though, Koi in ponds are used to having everyone who fishes that pond cast at them, so they are pretty spooky.

Your best bet is to fish some sweetcorn on a #6(not 6/0) circle hook and a carolina rig. Throw a handful out every hour and cast into the chum pile. Bring a net for sure. You might have grief from turtles depending on the pond. Hopefully you plan to release it back after catching.

_________________________Consultant for Splash BaitsConsultant for Deception Angling UKTournament Director for Wild Carp Club of Austin